Dual wheel assembly



Feb. 24,' 1942 ,cf s.l ASH` 2,274,353

DUAL WHEEL'ASSEMBLY Filed May 2o; '1959 s Sheets-sheet 1 VvvJ AT r y. To-RNEYs I ENR i@ MM f Feb. 24, 1942. c. s. AsH

v DUAL WHEEL' ASSEMBLY Filed May 2o, 19'39 3' sheets-sheet- :s

lig/E' TOR lllll 4f/05,56, @ma

Patented Feb. l24, 1942- l UNITED' STATES PATENT OFFICE DUAL WHEEL ASSEMBLY Charles S. Ash, Milford, Mich.

Application May 20, 1939, Serial No. 274,669'

s claims.

The invention relates to new and useful improvements in dirigible differential wheel assemblies, and more particularly to such improvements in dirigible differential wheel assemblies whereby camber is impart-ed or permitted to the Wheels.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practicev with the invention, the same being realized To these ends there is provided, as a present preferred embodiment, dirigible differential front wheels, freely relatively rotatable on an integral which may be mechanical or geometrical, the

and attained by means of the instrumentalitics Y and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to-herein and constituting apart hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Fig. 1 is a partial horizontal plan and section through a left-hand dual wheel assembly embodying the invention;

Fig. 2 is an enlarged fragmentary detail elevation, with parts in section of the steering knuckle and Wheel spindle and end of the axle beam of Fig. 1;

Fig. 3 is a section on line 3--3 of Fig. 2; Fig-4 is a view similar to Fig. 2 but showing a somewhat different form of'mechanism;

Fig. 5 is a section on line 5-5 of Fig. 4;-

Fig. 6 is a View similar to Fig 2 but showing another different form of the mechanism; Fig. 7 isa section on line 'I-'I of Fig. 6; Fig. 8 is a section on line 8 8 of Fig. 6; and Fig. 9 is a section'similanto Fig. 7 but showing a modification.

Objects of the invention are4 to provide for or effect a limited or desired amount of camber matically effecting camber to conform to variations in the road bed -so as to impose equal load and wear on both wheels; to providefor automatic variation in the caster so that adiiferent caster will be had for forward motion and for v reverse motion, and the reverse steering thereby-be rendered more stable.

.knuckle and spindle being angularly movable about the king pin axis by the steering gear. To eect desired camber, whether automatic or settable camber is desired, the king pin is mounted to have limited vertical angular movement relatively to the axle bar, about a substantially supporting point or horizontal axis,` which may be either a pivotal or spherical support for the king pin. This relative movement of the king pin in a vertical plane may be in a fixed plane or in planes varying with the steering movements of the knuckle. With the automatically settable camber, the king pin is resiliently held to a normal position about said axis, but has limited angular movement from that position, and if desired, in a plurality of directions, and by the cambering action thus obtained the side-by-side tires are allowed to conform to the road bed and thereby uniform action is obtained as to loading wear, traction, steering, while the -wheels are freely rotatable with respect to each other; and

vention illustrated by way of example in the accompanying drawings, a wheel spindle I has integral therewith a yoked knucklehaving a body portion 2 and horizontally-extending arms 3 and 4, there being a connection 5 between the lower arm and the steering mechanism which may be of usual form. i

The embodied form of side-by-side differential Wheels rotatably mounted on the spindle I comprises an outboard wheel having a dished web I I fastened to the flat outer face of a hub I2 by screw bolts I3, the hub I2 encircling the spindle I. Between the hub I2 and the spindle I are two spaced apart inclined roller bearings I5 and I6, which may be of suitable or known form. The inner ring I1 of inner bearing I6 abuts on its inner face on a flange' or shoulder I8 integral with spindle I and the outer face of the outer ring I9 abuts on a shoulder 20.formed in hub I2. The outer ring 23 of outer bearing I5 abuts at its inner face on a shoulder 24 on hub I2, and

outer face of inner ring 25 of this bearing abuts on a nut 26 screw-threaded on the end of spindle l. The inboard wheel comprises a dished web 3| integral with which is a dished offset hub, having two cylindrical bearing surfaces 32 and 33, which are journaled on corresponding cylindrical surfaces on the exterior of hub |2 with suitable interposed bushings 34 and 35. Braking means are provided for each Wheel, the outboard wheel having a brake drum 4| which is bolted to a ange 42, integral with and extending outwardly from the inner end of the inner wheel hub I2, and an expansible brake shoe 43 is mounted within the drum 4| and is provided with suitable actuating means. The inboard wheel has a brake drum- 48 having an integral, outwardly-extending annular lip 49 abutting on the inner flat annular face of wheel 3| and fastened thereto by screw bolts 58. Drum 48 likewise has an expansible brake shoe 5| operated by suitable means. A dished protecting shield 52 for the brake mechanism is provided, which is centrally internally apertured, and adjacent to said aperture is fastened to and supported from a disc 53 integral with wheel Aspindle I by screw bolts 54.

In the embodied form of camber-efecting means a universal joint is provided between the steering knuckle and axle beam end for effecting relative rotary movement between them, whereby automatic cambering may be effected concurrently with the usual steering control. As eme bodied, and referring particularly to Figs. 1, 2 and 3, an axle beam 6| has an enlarged end 62, fitting within the spaced-apart arms 3 and 4 of the steering knuckle, the end 62 having a convex spherical top bearing surface 63 and a bottom concave spherical bearing surface 64. The bearing surface 64 rests upon a ball 65 which is supported in a concave spherical seat in the inner end of a screw-threaded plug 66, screw-threaded into the arm 4'of the knuckle and held in place by a nut 61. Thus these spherical bearing surfaces between the knuckle and axle beam serve as a pivotal or universal bearing between them, relative rotary movement about a substantially vertical axis permitting steering and relative rotary movement about a substantially horizontal axis effecting automatic or settable camber. A resilient washer -68 is interposed between the bottom of the axle bar end 62 and the top surface of the yoke arm 4, a central aperture therein encircling the ball 65. In the upper arm 3 of the steering knuckle is an elongated, preferably rectangular, aperture 1|, within which is slidably fitted a block 12, the block being'shorterthan the aperture to have slidable playA longitudinally. A king pin 14 is screw-threaded into the upper face of the head 62 of the axle bar and extends upwardly through an internal cylindrical opening in the block 12, a bushing 15 being interposed between the pin and block. The lower face of the block 12 is concavely spherical and rests upon the con'- vex spherical surface 63 of the head 62. In rec- V,tangular opening 1|, in the space at either end of block 12 are resilient pads 11 and 18, held in place by metal casings 19 and 88, the pads acting as resilient stops to limit the movement of block 1.2 at the ends of its path. With this construction, as the wheels pass over the road surface, wheel spindle I has angular vertical play to a limited extent, the steering knuckle rotating on its universal bearing and about the center of ball 65, the spindle and knuckle having relative movement with respect to the king pin about the center of the ball as a geometrical pivot point. In

ltires when the wheels are steered about an in- -circular recessed portion. 81, formed in the top face of a self-alining block 88, having a convex spherical bottom face 89 resting on a correspond-l ing concave spherical face 98 formed in the inner face of screw plug 66, which is screw-threaded into arm 4 of the steering knuckle. On the eX- terior end of arm 3 of the knuckle ls a boss 93, into which is threaded a screw-bolt 94, the inner end of which engages a depressed seat in the side of block 12. Within aperture 1|, at the outer end thereof opposite the lscrew-bolt 94, is an insertable and removable shim 96, which is held in position by a laterallyeextending lip along the top edge which overlies the top of yoke 3. By using shims of different thicknesses, and by turning the screw bolt 94 to press the block 12 firmly against the shim, various desired degrees of camber may be imparted to the spindle, the knuckle having slight movement on the spherical surfaces 63 and 98, the thrust bearing participating in the relative movement of the steering knuckle and axle bar during the steering movement.

In Figs. 6, 7 and 8. is shown another form of the automatic camber effecting mechanism wherein a king pin |8| has an enlarged flat-sided base |82. The base |82 is located within a cylindrical opening in lower arm 4 of the steering knuckle, with considerable side play. The base |82 is pivotally supported on a bolt |83, which 'king pin. Block I|8 has a concavely spherical bottom which rests on the convex spherical top 63 of the axle beam head, block ||8 thus having considerable sliding movement on its support 63 to effect required camberng. Compression pads ||4 are provided at either side' of the block ||8 to resiliently limit its sliding movement similar to pad 11 of the previously described form. Ball bearings 86 are provided at the bottom of the cylindrical opening 62, the construction thereof being in general similar to that shown and described in connection with Fig. 4.

In Fig. 9 a modified form is shown which permits both variable cambering and castering action as required. The general structure of the king-pin joint is the same as, or similar to, that shown in Fig. 2, but the mounting of the king pin in the upper yoke arm 3 is changed to permit variable cambering and castering action of the wheels. To this end, block |12 has all around, resilient floating fit in the opening- |1|, the vertical'edges of the block |12 being beveled to afford considerable play and also to allow for universal movement of the block relatively to the opening. Resilient means are provided on all four sides to limit the movement of block |12,

and for this purpose the opening |1| has on all four sides a recess in each of which is seated a vcasing |80, each holding a resilient pad |11 or |18, any one or two of which, acting concurrently, will permit and also limit the lateral movement of the block and consequently the cambering and castering actions. The universal move.- ment of the block |12 provides both cambering and castering movement', the camber of the wheel spindle being proportional to the resultant of the movement of the king pin in the direction .l

of the wheel spindle, and the transverse resultant movement of the king pin provides automatic variation in the caster so that adifferent caster .will be had for forward movement and reverse movement ofthe vehicle and the reverse steering thereby be rendered more stable.

It will be understood that my adjustable king pin structure which provides automatic camber or for setting a predetermined ilxed camber,

, can be adapted to all types of front axle beam and knuckle structures. The pivoting point can be arranged atthe, bottom portion of the knuckle as shownherein or can be reversed and located at the top portion of the knuckle; and by raisin said axle beam end, and forming a substantially vertical axis-for the yoke, a spherical supporting seat coaxial with the king pin in the lower arm of said yoke, a block in which the king pin is mounted, said block being slidably.

mounted in anelongated opening in the upper arm o'f said yoke, and resilient means within the ends of said elongated opening and resiliently yieldable under pressure from said slidable block.

3. A dual dirigible front wheel assembly rincluding in combination a wheel spindle and yoked steering knuckle, dual wheels mounted on said spindle, an axle beam with its end within said yoke, a king pin mounted insaid axle beam end and forming a-substantially vertical axis lfor the yoke, a spherical -supporting s'eat coaxial with the king pin in the lower arm of said yoke, a block 'in which the king pin is mounted, said block being slidably mounted"in-an elongated opening =in the upper arm of said yoke, and means mounted on said upper yoke arm cooperating with said-slidable block to govern the posi` tion of -theblock n said opening` 4. A dual dirigible front Wheel assembly including in combination a wheel spindle and yoked steering knuckle, an axle beam with its end within said steering knuckle yoke, a king pin fixed to the axle beam and forming a vsubstantially vertical axis for the yoke, means interconnecting the king pin and steering knuckle yoke,

l and arcuate bearing surfaces between the upper ing or lowering the pivoting point for the camber action the amount of compensation for the two tires at the road bed is affected.

The invention in, its broader aspects is not limited to the specific mechanisms shown and described but departures may be made therefrom.

within the scope of the accompanying claims without departing from the principles of the invention and without sacriiicing its chief advantages. i

What I claim is: 1. A dual dirigible lfront wheel assembly including in combination a wheel spindle and yoked steering knuckle, dual wheels mounted on said yoke, a king pin mounted in said axle beam end and forming a substantially vertical axis for the yoke, a spherical supporting seat in .the lower arm of said yoke coaxial with the king pin, a block in which the king pin is mountedsaid block being slidably mounted in an elongated opening in the upper arm of said yoke, and resilient means within the ends of said elongated 2.1 dual dirigible front wheel assembly including in combination a wheel spindle and yoked steering knuckle, dual wheels mounted on said spindle, an axle beam with its end within said yoke, aspherical bearing between said beam and the upper arm of said yoke, a king pin mounted arm of the yoke and the axle beam and between the lower arm of the yoke and the axle beam for permitting pivotal movement of the spindle and spindle, an axle beam with its end within said wheels about a substantially horizontal axis.

5. A- dual dirigible front wheel assembly including infcombination a wheel spindle andl yoked steeringL knuckle, an axle beam with its end within said steering knuckle yoke, aking pin xed to the axle beam and forming a substantially vertical axis for the yoke, meansi'nterconyoked steering knuckle, a pair of wheels on the `opening and resiliently yieldable under pressure s from said slidable block.

.zontalaxia J spindle, an axle beam with its end within said steering knuckle yoke, a king pin ilxed to the axle beam between the two wheels and forming a substantially vertical axis for the yoke, means interconnecting the king pin and steering knuckle yoke, uand arcuate bearing surfaces between the upper arm of the yoke and the axle beam and between the lower arm 'of the yoke and the axle beam for permitting pivotal movement oi' the spindle and wheels about a substantially horicHARLEs s. Asn. 

